Navman was founded 5 years before TomTom but didn't become well-known until the 1990's.

Both companies are specialists in stand-alone GPS units, GPS software for Palm handhelds and Pocket PCs, and navigation systems for mobile phones.

Depending upon what model you want and where you shop for it, the Tom Tom and Nav Man start at around the same price, this will of coures only add to the difficult decision ahead!

We chose the two most popular models to compare...

Being the more "budget" model, the F20 misses out on extras like text-to-speech and MP3 playback, but it does have a unique pause function plus the aforementioned dedicated button for locating the nearest petrol station or car park. Other software features include the route summary view and both 2D and 3D map views, as well as day and night modes. When turning on the F20 for the first time, you're faced with several setup questions that include selecting a regional map and choosing between miles and kilometers. Entering your destination details is a slow process because the onscreen keyboard is rather small. We were impressed with how quickly the system could recalculate another route when we missed a turn and the voice guidance was easy to understand. We also rate their online technical support feature but there is still a customer service telephone number.

Measuring just 96mm by 82mm by 25mm and weighing 174 grams.

3.5-inch LCD screen with 320 x 240 pixels and 64,000 colours.

Anti-glare feature.

Integrated GPS antenna and SD card slot.

In-car charger, AC chargers, USB charger available

SiRFstarIII GPS chipset

266MHz processor

One of TomTom's highlights is their simple to use menu system, that's made even easier with the useful onscreen tips. Choosing a route has the options of quickest, shortest, or avoiding toll roads and congestion charge areas plus you can plan a route based on a desired arrival time. A nice touch is that, whilst driving, the unit's volume automatically adjusts depending on the speed of the car! There's an added option of displaying a compass on screen to help your orientation and there's access to TomTom's PLUS services which include safety camera alerts, weather reports and the new Buddies feature, which combines instant messaging and navigation that you can use to locate your friends.

As with Navman devices users can link the SatNav to a PC or MAC using the included software package. Here routes can be downloaded, trips can be reviewed  new maps can be loaded onto the SD card.

The TomTom One has Bluetooth to connect it to your mobile phone, but this is only for downloading data to the device, not hands-free calling as with later models.

Although the TomTom was quick to obtain a signal, it takes some time to recalculate routes so users may miss turns before the device has finished its calculation. It retains around two hours of battery life from a single charge.

Two great gadgets and in all honesty they both have there uses. The Navman is better value for money as it can come up slightly cheaper and has a larger 16:9 screen however the TomTom has loads of added features and, when you shop around, you can get the traffic master package included in the price whereas NavMan's traffic add-on can cost upto £100.

Based on popularity and compatibility...